Elastic plaster.



UNi'rEn STATES PATENT OFFICE.

HENRY .LEE CARTER, OF NEW YORK, N. Y.

ELASTIC PLASTERE V SPECIFICATION forming part of Letters Patent No.695,031, dated March 11, 1902.

Application filed July 24, 1901. fierlal No 69,589. ($peoimens.)

To all 1071,0112 it may concern:

Be it known that I, HENRY LEE CARTER, a

citizen of the United States, and a resident of the borough ofManhattan, in the city and county of New York and State of New York,haveinvented certain new and useful Improvements in ElasticPlasters', ofwhich the following is a specification.

My invention relates to the process of manufacturing elastic plaster forwalls, ceilings, pottery use, and the like and for use in the fine arts,for molding into statuary, and for any other purposes to which anyplasters are applicable.

By means of my invention I obtain a truly elastic plaster, one that ismore adhesive and tenacious than those commonly in use and admirablyadapted to withstand strains without cracking or buckling. It may bedirectly applied to lath, stone, brick, or even smoother surfaces. Thesimplicityof its manufacture and at practically the same cost asordinary and plain'calcined plasters makes it most desirable, inaddition to its elastic qualities. 7 My plaster may be used in the sameway as all grades of calcined plaster now in use; but the fact that itcan be used as before stated permits saving of expense in its use orapplication. For wall use in buildings the troublesome mixing of mortar,sand, lime, 650., may be entirely dispensed with. On account of theflexible and elastic nature of my prodnot a building may settle unevenlywithout cracking the plaster.

The invention relates, further and more especially,- to the productobtained by my process.

The first step in the process of manufacturing the product consists incalcining the natural gypsum-rock or its equivalents-as lime,marble-dust, and the like-by the usual methods. The next step consistsin subjecting the calcined substance to the operation of screening orbolting, reducing the substance to a fine powder, and obtaining animpalpable powder. The calcined plaster is thoroughly mixed withalthaea, commonly known as marshmallow-root, and dextrine. In place ofthe althzea any of its equivalents, as just herein-below noted, may beemployed-via, althaeo leaves or flowers, Althcea Tosca, Maltasyloestrz's, .Maloa. 'v-ulgarz's, Malta r0tundtfoZz'a, Hibiscusesculentus, Hibiscus abelmosc7ms,Htbiscus sabdctrzfia, Hibiscusrose-sincus'z's, Abitt'ilon aoiceimce. The ingredients are placed in amixer, mortar, or any vessel or piece oflmachinery, whereby a mixingresults equivalent to trituration. g V

The manner of using mycompouud (elastic plaster) is the same'as thatemployed with any and all ordinary plastersnamely, by adding waterto thedesired proportion justv before application to obtain the requisiteconsistency. v

Care should be taken to mix together proper proportions of theingredients, although my invention is not limited to a mere matter ofproportion. For good results there may be two thousand'pounds ofcalcined gypsum or calcic sulfate, six pounds of altheea ormarshmallow-root, and six pounds of dextrine, or their equivalents. V

I sometimes add a small portion of gelatin to the mixture. I a

I have found by numerous experiments that althaea and dextrine exertpositive and negative effects on the calcined gypsum, the althaearetarding and the dextrine hastening the setting, and these opposingeffects enables me to easily combine the ingredients to obtain a plasterwhich will set in a predetermined in terval of time, and both have to bepresent to obtain my product.

Having described my invention, I desire to secure by United StatesLetters Patent and claim o.

1. Aplaster consisting of a mixture of a base of calcined gypsum,althzea, and dextrine.

2. A plaster consisting of a mixture of a base of calcined gypsum,althaea, dextrine and gelatin;

3. A plaster consisting of a mixture of abase of calcined gypsum,in theproportion of about

